The recovery of metals from ore is made more difficult by the presence of other metals in the ore. Chemical processes for recovery of precious metals are disclosed in U.S. Pat. Nos. 4,740,243, 4,752,332, and 4,765,827. None of these patents disclose processes which come close to the recovery efficiency for metals achieved with the subject invention process.
Biological recovery of silver and manganese from refractory ore is disclosed in Gupta, A., and H. L. Ehrlich in Jour. of Biotechnology (1989) 9: 287-304. Disclosed is the use of a mold, Penicillium, incubated aerobically, without a chelator with the ore. After 5 weeks incubation, a 23.5% solubilization of Mn and 26.5% solubilization of silver was achieved. This result is not considered to be an efficient silver or manganese recovery.
Soils contaminated with heavy metals, e.g., plutonium, uranium, and the like, pose severe health problems to humans and animals. Thus, the removal of these heavy metal contaminates is a desirable goal. The subject biological process accomplishes this desirable goal.